Question

Вниз по течению катер идёт 2ч, а вверх - 3ч. Сколько времени между теми же пунктами будет плыть бревно?

Answer 1

Здесь должна быть скорость реки 

х -скорость катера

у -скорость реки

(х+у )*2=(x-y)*3

2x+2y=3x-3y

2x-3x=-3y-2y            -x=-5y    x=5y           скорость катера больше скорости реки в 5 раз

Если катер проплыл по течению реки за 2 часа, то бревно - 5*2=10 часов.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Answer 2

Calculating Time for the Log

To calculate the time it takes for the log to float downstream and upstream, we can use the formula:

Time = Distance / Speed

Given that the time downstream is 2 hours and upstream is 3 hours, we can use these values to calculate the speed of the boat.

Calculating Speed

Let's denote the speed of the boat as S and the speed of the current as C. The speed of the boat downstream is S + C and the speed of the boat upstream is S - C.

Using the given times and the formula Time = Distance / Speed, we can set up the following equations:

Downstream: 2 = Distance / (S + C)

Upstream: 3 = Distance / (S - C)

By solving these equations, we can find the values of S and C.

Solving the Equations

To solve for S and C, we can use the method of substitution or elimination to find the values that satisfy both equations.

Let's calculate the speed of the boat and the speed of the current using the given information.